The present invention relates to a hub for at least partially muscle-powered vehicles and in particular for two-wheeled vehicles. Such a hub comprises a fixed hub axle, a hub body rotatable relative thereto, a rotatable driving device, as well as a toothed disk freewheel. Such a driving device may for example be configured as a rotor to which a sprocket or else a set of sprockets may be mounted for transmitting the driving torque via the driving device to the hub body. Optionally the driving device may be configured integrally with a sprocket or a set of sprockets.
In the prior art, hubs have become known which provide a freewheeling function via a toothed disk freewheel. Thus, DE 198 476 73 A1 discloses a rear wheel hub having a toothed disk freewheel wherein two toothed disks are provided at their side faces with axial toothings meshing with one another. In the driving direction, the torque applied is reliably transmitted while in the reverse rotational direction, the toothed disks axially diverge from one another, thus providing the freewheeling function. To ensure reliable engagement of the toothed disks in the driving direction, both of the toothed disks are urged toward one another by means of coil springs. The known hub operates reliably and has been tried and tested. Good responsivity can be achieved by selecting a suitable spring rigidity of the press-on springs. There is a certain disadvantage though in that friction arises in the freewheeling state at the toothed disks due to the toothed disks gliding upon one another when the axial toothings are urged away from one another. Moreover, noises are emitted which are not always perceived as agreeable. The biasing springs apply a certain force already in the engaging position for retaining the two toothed disks in secure engagement. This press-on force and thus the friction increases further as the freewheeling function begins and the biasing springs are urged away from one another while being compressed.